Impact of ultrasound process on cassava starch nanoparticles and Pickering emulsions stability.

Using green techniques to convert native starches into nanoparticles is an interesting approach to producing stabilizers for Pickering emulsions, aiming at highly stable emulsions in clean label products. Nanoprecipitation was used to prepare the Pickering starch nanoparticles, while ultrasound technique has been used to modulate the size of these nanoparticles at the same time as the emulsion was developed. Thus, the main objective of this study was to evaluate the stabilizing effect of cassava starch nanoparticles (SNP) produced by the nanoprecipitation technique combined with ultrasound treatment carried out in the presence of water and oil (more hydrophobic physicochemical environment), different from previous studies that carry out the mechanical treatment only in the presence of water. The results showed that the increased ultrasound energy input could reduce particle size (117.58 to 55.75 nm) and polydispersity (0.958 to 0.547) in aqueous dispersions. Subsequently, Pickering emulsions stabilized by SNPs showed that increasing emulsification (ultrasonication) time led to smaller droplet sizes and monomodal size distribution. Despite flocculation, long-term ultrasonication (6 and 9 min) caused little variation in the droplet size after 7 days of storage. The cavitation effects favored the interaction between oil droplets through weak attraction forces and particle sharing, favoring the Pickering stabilization against droplet coalescence. Our results show the potential to use only physical modifications to obtain nanoparticles that can produce coalescence-stable emulsions that are environmentally friendly.

Effect of processing (cutter versus continuous emulsifier) and sodium reduction on the physicochemical properties of bologna sausages.

BACKGROUND: Overcoming the impact of sodium reduction in the properties of emulsified sausages is a current challenge in the production of healthier meat products. Because the emulsifying process play a key role in the stability of sausages, the present study aimed to evaluate the effects of two mechanical emulsifying systems (cutter versus continuous emulsifier) and two levels of sodium chloride (2.50 and 1.25%) on the physicochemical characteristics of bologna sausages. RESULTS: A reduction of sodium increased the L* value and reduced the a* value, and also decreased the protein extraction yield in sausages produced in the cutter system. Moreover, the emulsion stability of reduced sodium batter was increased by cutter emulsification (F50C). On the other hand, the continuous emulsifier process did not decrease the extraction of myofibrillar proteins in F50E (sodium reduced treatment), resulting in minimal impact on emulsion stability and an increase in hardness in reduced-sodium sausages. CONCLUSION: Therefore, to produce low-sodium sausages, the continuous emulsifier was more effective producing batters with increased extracted myofibrillar proteins, improving the structure and functionality of myofibrillar proteins compared to the cutter process. © 2023 Society of Chemical Industry.

Antioxidant and emulsifying properties of a galactose-rich heteropolysaccharide from Plinia cauliflora peels.

In this study functional properties of a galactose-rich heteropolysaccharide (GH) were accessed. The bands of a galactose-rich polysaccharide were found in FTIR spectra, including those from the fingerprint region. GH was characterized as a dark-red material (L* 25.86 ± 0.75, a* 9.46 ± 1.01, b* 0.65 ± 0.14, Chroma 9.48 ± 1.02) with antioxidant activity of 21.5 ± 0.08, 12.1 ± 0.06 and 0.46 ± 0.04 mmol Trolox Eq/mg GH in FRAP, DPPH and ABTS, respectively. GH presented 44.9% of esterification degree and 10.73 ± 0. 01 mg of GAE/g. The production parameters of GH emulsions (GH concentration, time and ultrasound power) were optimized using a 23 Central Composite Rotatable Design (CCRD). Emulsion droplets presented particle size (d µm) varying from 0.823 ± 0.065 to 1.926 ± 0.151, polydispersity index (PDI) from 0.10 ± 0.05 to 0.40 ± 0.01 and zeta potential from -29.25 ± 3.98 to -33.75 ± 1.77. Finally, the high emulsifying activity (EA) (96.67%) and emulsion stability (ES) (97.44%) allow suggesting that GH is a promising polysaccharide for food applications.

Use of physical processes to maximize goat milk cream hydrolysis: Impact on structure and enzymatic hydrolysis.

This study evaluated the use of ultrasound (US), high-shear dispersion (HSD), stirring (ST), and low or high pressure homogenization (LPH or HPH) technologies to modify the goat milk cream (GMC) structure, focusing on improving the enzymatic hydrolysis of its lipids. The GMC structure was evaluated, as well as its creaming and emulsion stability index (ESI). The processed GMC was hydrolyzed by lipase at 50 °C for 300 min, and the fatty acids concentration (FAC) was evaluated over the reaction. ST, HPH, and HSD showed âˆ¼ 90% lower emulsion destabilization, 10 times higher ESI, and smaller fat globule size than unprocessed GMC. The pretreatments increased the hydrolysis rate up to 2.4 times and the final FAC up to 8.7 times. ST (4 min), HPH (40 MPa) and HSD (5 min/ 25,000 rpm) showed the best results, which were correlated with the changes in the GMC structure. The results suggest that the physical treatments impacted the substrate structure, favoring enzyme activity and accelerating the hydrolysis degree. Therefore, the application of physical processes can be an interesting strategy to enhance the hydrolysis of GMC, aiming to produce compounds of industrial interest.

Encapsulation of Pomegranate Peel Extract (Punica granatum L.) by Double Emulsions: Effect of the Encapsulation Method and Oil Phase.

Pomegranate peel is an agro-industrial waste that can be used as source of punicalagin, a polyphenolic compound with several beneficial effects on health. Since, once extracted, punicalagin is prone to degradation, its encapsulation by double emulsions can be an alternative to protect the active compound and control its release. The aim of this investigation was to evaluate the feasibility of encapsulating pomegranate peel extract (PPE) in double emulsions using different types of oils (castor, soybean, sunflower, Miglyol and orange) in a ratio of 70:30 (oil:PPE) and emulsification methods (direct membrane emulsification and mechanical agitation), using polyglycerol polyricinoleate (PGPR) and Tween 80 as lipophilic and hydrophilic emulsifiers, respectively. Direct membrane emulsification (DME) led to more stable emulsions during storage. Droplet size, span values, morphology and encapsulation efficiency (EE) were better for double emulsions (DEs) prepared by DME than for mechanical agitation (MA). DEs formulated using Miglyol or sunflower oil as the oily phase could be considered as suitable food grade systems to encapsulate punicalagin with concentrations up to 11,000 mg/L of PPE.

Synergic effects of ultrasound and ionic liquids on fluconazole emulsion.

The aim of this work was to evaluate the influence of US on the properties of the fluconazole emulsions prepared using imidazolium-based ILs ([Cn C1im]Br). The effects of the preparation method (mechanical stirring or US), US amplitude, alkyl chain length (of [C12C1im]Br or [C16C1im]Br), and IL concentration on the physicochemical properties were evaluated. Properties such as droplet size, span index, morphology, viscosity encapsulation efficiency, and drug release profile were determined. The results showed that US-prepared emulsions had a smaller droplet size and smaller polydispersity (Span) than those prepared by mechanical stirring. Additionally, the results showed that emulsions prepared with [C16C1im]Br and US had spherical shapes and increased stability compared to emulsions prepared by MS, and also depended on the IL concentration. The emulsion prepared by US at 40% amplitude had increased encapsulation efficiency. US provided a decrease in the viscosity of emulsions containing [C12C1im]Br; however, in general, all emulsions had viscosity close to that of water. Emulsions containing [C16C1im]Br had the lowest viscosities of all the emulsions. The emulsions containing the IL [C16C1im]Br had more controlled release and a lower cumulative percentage of drug release. The IL concentration required to prepare these emulsions was lower than the amount of conventional surfactant required, which highlights the potential synergic effects of ILs and US in preparing emulsions of hydrophobic drugs.

Ultrasound and low-levels of NaCl replacers: A successful combination to produce low-phosphate and low-sodium meat emulsions.

Meat emulsions were made with 50% of phosphate level commonly used in the meat industry, and 0, 25, and 50% NaCl reduction. In addition, salt replacers (KCl, CaCl2, or MgCl2) were used in the formulations with 25 and 50% salt reduction, corresponding to 10 and 20% of the total amount of salts added, respectively. After embedding in casings, the samples were sonicated (25 kHz and 230 W) in an ultrasonic bath (US) at 20 °C for 0, 18, and 27 min. The addition of CaCl2 or MgCl2 impaired (P < .05) the technological properties of the low-sodium samples. Defects caused by NaCl reduction were not eliminated by 18-min US. However, the combination of KCl and 27-min US eliminated the technological defects caused by the 50% NaCl reduction, with no major impact on lipid oxidation during storage (21 days/4 °C), as observed in the TBARS and sensory profile results. Therefore, it is possible to produce low-phosphate and low-sodium meat emulsions.

How drying methods can influence the characteristics of mucilage obtained from chia seed and psyllium husk / Como os métodos de secagem podem influenciar as características da mucilagem obtida de sementes de chia e casca de psyllium

The influence of drying methods (oven drying at 50 °C, and freeze drying) on the centesimal composition, functional characteristics and rheological properties of mucilage obtained from chia seed and psyllium husk were investigated. Results showed that high temperature of oven drying reduced fiber content, solubility, emulsion activity and emulsion stability of mucilage. All samples showed pseudo plastic behavior, with the best result produced by Heschel-Bulkley and Power Law models of chia and psyllium mucilage, respectively. These results will be helpful in selecting suitable drying methods depending on the functional and rheological properties desired of the chia and psyllium mucilage in a food product.(AU)

Este estudo teve como objetivo avaliar a influência dos métodos de secagem (secagem em estufa a 50 °C e liofilização) sobre a composição centesimal, características funcionais e propriedades reológicas da mucilagem obtida a partir de sementes de chia e casca de psyllium. Os resultados mostraram que a alta temperatura de secagem em estufa reduziu o teor de fibras, a solubilidade, a atividade da emulsão e a estabilidade da emulsão das mucilagens. Todas as amostras apresentaram comportamento pseudoplástico, com o melhor ajuste produzido pelos modelos Heschel-Bulkley e Power Law das mucilagens de chia e psyllium, respectivamente. Estes resultados serão úteis na seleção do método de secagem adequado, dependendo das propriedades funcionais e reológicas desejadas das mucilagens de chia e psyllium.(AU)

Reducing phosphate in emulsified meat products by adding chia (Salvia hispanica L.) mucilage in powder or gel format: A clean label technological strategy.

This study evaluated the functional properties of chia mucilage powder (MCP) and gel (MCG) as a phosphate replacers in low-fat Bologna sausages. Four treatments were produced without phosphates (F1-2% MCP; F2-2% MCG; F3-4% MCP; F4-4% MCG) and two with 0.25% phosphate (F5-2% MCG and F6-4% MCG) besides control (20%-fat-0.5% phosphate). Samples containing mucilage were less firm and less chewy on day 0, except F3. Treatments containing 2% MCG were judged acceptable and provided better emulsion stability than those with MCP. Adding 4% MCP or MCG resulted in Bolognas with lower relaxation times and more restricted mobility and lowest sensorial acceptance characterized by the terms light brown and dark pink color (F4). The microscopy images exhibited less cohesive structure in treatments with 4% of MCG, suggesting the formation of a weaker bound protein network. Chia mucilage gel at 2%, due to its functional properties, has proven to be a feasible strategy to substitute 50% phosphate in low-fat Bologna sausages.

Ultrasound and basic electrolyzed water: A green approach to reduce the technological defects caused by NaCl reduction in meat emulsions.

Meat emulsions were prepared by replacing water with basic electrolyzed water (BEW) and reducing NaCl content by 0, 10, 20, 30, 40, and 50%. The emulsions were sonicated in an ultrasound bath (25 kHz, 175 W, normal mode) for 0, 10, and 20 min. The physicochemical (pH, redox potential, water activity, and color parameters) and technological (cooking yield, emulsion stability, and texture) characteristics were evaluated. The US operation time of 20 min improved the emulsion stability, cooking yield, and texture of the emulsions with 10% and 20% NaCl reduction. The BEW-treated emulsions exhibited good fat retention and moderate water retention capacity. The combination of US and BEW for 20 min provided good emulsion stability and cooking yield for the formulations with up to 30% NaCl reduction, which exhibited texture profile similar to the control (0% NaCl reduction). Therefore, it is possible to produce reduced-salt meat emulsions using the combination of US and BEW.

Application of arginine and histidine to improve the technological and sensory properties of low-fat and low-sodium bologna-type sausages produced with high levels of KCl.

Low-fat bologna sausages were made with the replacement of 60% NaCl by KCl and with the addition of arginine and histidine alone or in combination. The technological and sensory properties were evaluated. The replacement of NaCl by KCl did not significantly affect the color parameters L*, a*, and b*. However, the emulsion stability, the texture profile, and the sensory quality were impaired by the salt substitution. The addition of arginine and histidine alone or in combination was effective to reduce the defects caused by the addition of KCl. The present study demonstrated that bologna sausages with reduced sodium content (≈40%) and acceptable technological and sensory properties can be produced using 1% NaCl, 1.5% KCl, 1% arginine and 0.2% histidine.

How drying methods can influence the characteristics of mucilage obtained from chia seed and psyllium husk / Como os métodos de secagem podem influenciar as características da mucilagem obtida de sementes de chia e casca de psyllium

ABSTRACT: The influence of drying methods (oven drying at 50 °C, and freeze drying) on the centesimal composition, functional characteristics and rheological properties of mucilage obtained from chia seed and psyllium husk were investigated. Results showed that high temperature of oven drying reduced fiber content, solubility, emulsion activity and emulsion stability of mucilage. All samples showed pseudo plastic behavior, with the best result produced by Heschel-Bulkley and Power Law models of chia and psyllium mucilage, respectively. These results will be helpful in selecting suitable drying methods depending on the functional and rheological properties desired of the chia and psyllium mucilage in a food product.

RESUMO: Este estudo teve como objetivo avaliar a influência dos métodos de secagem (secagem em estufa a 50 °C e liofilização) sobre a composição centesimal, características funcionais e propriedades reológicas da mucilagem obtida a partir de sementes de chia e casca de psyllium. Os resultados mostraram que a alta temperatura de secagem em estufa reduziu o teor de fibras, a solubilidade, a atividade da emulsão e a estabilidade da emulsão das mucilagens. Todas as amostras apresentaram comportamento pseudoplástico, com o melhor ajuste produzido pelos modelos Heschel-Bulkley e Power Law das mucilagens de chia e psyllium, respectivamente. Estes resultados serão úteis na seleção do método de secagem adequado, dependendo das propriedades funcionais e reológicas desejadas das mucilagens de chia e psyllium.

Alpha-cyclodextrin as a new functional ingredient in low-fat chicken frankfurter.

1. The current consumer preference for healthier meat products is associated with less additives in manufacturing (so-called 'clean-label') or the addition of non-meat ingredients with functional properties, recognised as improving specific technological properties in meat products.2. This study evaluated the effect of the addition of alpha-cyclodextrin and wheat fibre to low-fat chicken frankfurters containing 35% mechanically deboned chicken meat on the technological and sensorial properties during refrigerated storage.3. The results showed that the addition of dietary fibres (alpha-cyclodextrin and wheat fibre) in low-fat chicken frankfurters improved emulsion stability, hardness, chewiness and reduced cohesiveness.4. Alpha-cyclodextrin helped the retention of fat globules in the microstructure and affected colour in the sensorial evaluation.5. The use of alpha-cyclodextrin, in combination with wheat fibre, as a new ingredient to substitute fat in emulsified meat products containing mechanically deboned chicken, improved emulsion stability and texture.6. Alpha-cyclodextrin and wheat fibre were effective in contributing to fat reduction without affecting the sensory properties of the product.

Data on ICP OES and emulsion stability of Bredemeyera floribunda root extract: Medicinal plant used by the Brazilian rural population to treat snakebites.

Bredemeyera floribunda Willd (B. floribunda) is a medicinal plant used by the Brazilian rural population to treat snakebites, but there are no data on the elemental composition and stability of the emulsion of extract of this plant. In this article, we present for the first time data on contents obtained the roots of the medicinal plant B. floribunda by using inductively coupled plasma optical spectrometry (ICP OES), as well as the data on preliminary stability tests of emulsions formulated with aqueous extract of this plant. The first set of data shows a total of 13 elements (Al, Ca, Cr, Fe, K, Mg, Mn, Na, Ni, P, Cu, Se and Zn) detected in the roots of the plant. The second set of data shows that the extract data of the B. floribunda roots presented an emulsifying potential. In addition, the article provides information on the heating program for microwave oven digestion and ICP OES operating conditions. The data presented make way for nutritional and toxicological studies involving the roots of B. floribunda. The data on the cataloging of the plant can be found in the deposit nº 54366 of the Herbarium of the Federal University of Mato Grosso do Sul, available in www.splink.org.br/form?lang=pt&collectioncode=CGMS.

The effect of specialty salts on cooking loss, texture properties, and instrumental color of beef emulsion modeling systems.

The purpose of this study was to evaluate the functional properties of specialty salts when incorporated into formulations of meat emulsions. Beef emulsion modeling systems were formulated with three types of specialty NaCl salts or a commercially sourced white NaCl salt at three different inclusion levels (0.70%, 1.00%, and 1.30%). Cooking loss, emulsion stability, proximate composition, pH, texture profile, and instrumental color of the emulsions were evaluated with three independent replications. Emulsion stability and cooking loss were primarily affected (P < 0.01) by salt inclusion level, while salt type was not affected (P > 0.12). Stability increased and cooking loss decreased as salt inclusion level increased (linear P < 0.01). Hardness, springiness, gumminess, and chewiness of emulsions increased as salt inclusion level increased for all the treatments and were greatest (P < 0.0001) in all treatments at 1.30% salt inclusion level. Overall salt inclusion level, rather than salt type, had significant effects on water holding ability and emulsion stability.

Studied of Defatted Flour and Protein Concentrate of Prunus serotine and Applications.

Prunus serotine seed, was processed to produce a defatted flour (71.07 ± 2.10% yield) without hydrocyanic acid. The total protein was 50.94 ± 0.64%. According to sensory evaluation of cookies with P. serotine flour, the highest score in overall impression (6.31) was at 50% flour substitution. Its nutritional composition stood out for its protein and fiber contents 12.50% and 0.93%, respectively. Protein concentrate (PsPC) was elaborated (81.44 ± 7.74% protein) from defatted flour. Emulsifying properties of PsPC were studied in emulsions at different mass fractions; ϕ = 0.002, 0.02, 0.1, 0.2, and 0.4 through physicochemical analysis and compared with whey protein concentrate (WPC). Particle size in emulsions increased, as did oil content, and results were reflected in microscope photographs. PsPC at ϕ 0.02 showed positive results along the study, reflected in the microphotograph and emulsifying stability index (ESI) test (117.50 min). At ϕ 0.4, the lowest ESI (29.34 min), but the maximum emulsifying activity index (EAI) value (0.029 m2/g) was reached. WPC had an EAI value higher than PsPC at ϕ ≥ 0.2, but its ESI were always lower in all mass fraction values. PsPC can compete with emulsifiers as WPC and help stabilize emulsions.

Whey protein concentration by ultrafiltration and study of functional properties / Concentração de proteínas de soro por ultrafiltração e estudo das propriedades funcionais

This paper aim to evaluate the ultrafiltration (UF) process for constituents recovery from whey. Sequences of factorial designs were performed by varying temperature (5 to 40°C) and pressure (1 to 3 bar), to maximize the proteins concentration using membrane of 100kDa in dead end system. Based on the best result new experiments were performed with membrane of 50kDa and 10kDa. With the membrane of 50 the protein retention was about 3 times higher than the membrane of 100kDa. The concentrated obtained by UF membrane of 10kDa, 10°C and 2 bar in laboratory scale showed a mean protein retention of 80 %, greater protein solubility, emulsion stability and the identification of β-lactoglobulins (18.3 kDa) and α-lactalbumin fractions (14.2kDa). Therefore, the use of membrane of 100 and 50kDa are became a industrially recommendable alternatives to concentration of whey proteins, and/or as a previous step to the fractionation of whey constituents using membrane ≤10kDa, aiming at future applications in different areas (food, pharmaceutical, chemical, etc.).(AU)

O objetivo do estudo foi avaliar o processo de Ultrafiltração (UF) na recuperação dos constituintes do soro de leite. Planejamentos fatoriais sequenciais foram realizados, variando a temperatura (5 a 40°C), a pressão (1 a 3 bar) e visando maximizar a concentração de proteínas usando membrana de 100kDa em sistema dead end. Baseados nos melhores resultados, foram realizados experimentos com de 50kDa e 10kDa. Em relação a membrana de 50kDa, a retenção de proteínas foi cerca de três vezes maior em relação a membrana de 100kDa. O concentrado obtido por membrana UF de 10kDa, 10°C e 2 bar, em escala laboratorial, mostrou uma retenção média de proteína de 80%, maior solubilidade protéica, estabilidade da emulsão e a identificação das frações β-lactoglobulins (18.3kDa) e α-lactalbumin (14.2kDa). Portanto, o uso de membranas de 100 e 50kDa são alternativas recomendáveis industrialmente à concentração de proteínas de soro de leite, e/ou como etapa anterior ao fracionamento de constituintes do soro usando membrana ≤10kDa, visando aplicações futuras em difentes áreas (alimentícia, farmacêutica, química, etc).(AU)

Impact of oil type and WPI/Tween 80 ratio at the oil-water interface: Adsorption, interfacial rheology and emulsion features.

The relationship between the composition and structure of food emulsions was evaluated from the effect of a mixture of emulsifiers Whey protein (WPI) - Tween 80 (T80) and the oil phase features, such as chain length and unsaturation degree (sunflower oil, a long chain triacylglycerol - LCT or NEOBEE® 1053, a medium chain triacylglycerol - MCT). Emulsions with LCT showed higher droplet size than MCT as a consequence of its higher viscosity. All emulsions exhibited shear thinning behavior, but the viscosity was influenced by their interface composition. An occurrence of the destabilization mechanism by creaming was observed in turbidimetric measurements, but no visual phase separation could be observed, indicating a good kinetic stability after a 7-day storage. The initial interfacial tension of the water-LCT or water-MCT oil was about 25 mN/m, but the WPI addition (1% w/w) reduced the initial interfacial tension to approximately 20 mN/m. The increase of T80 concentration led to a decrease of the interfacial tension, reaching a value around 10 mN/m in systems with pure T80. The curves of interfacial tension of systems with LCT or MCT showed differences in the decay rate of tension over time. These differences were attributed to characteristics of the oil phase (hydrophobicity, unsaturation degree, presence of impurities) and the different proportions of each emulsifier within the mixture of emulsifiers. Finally, a higher viscoelastic interface was observed in LCT emulsions, which were mainly stabilized by WPI molecules. Such molecules presented a higher resistance to the displacement due to the competitive adsorption phenomenon, since the LCT is a more hydrophobic oil. On the other hand, the interface with MCT and a higher T80 concentration was less viscoelastic due to an easier displacement of WPI from the interface and the replacement by T80. The results indicate that T80 can be used in combination with WPI to produce emulsions with good stability and lower concentration of synthetic compounds. Lastly, the interfacial layer composition is not only dependent on the WPI-T80 ratio in the bulk phase, but also on the oily phase features. These results provide a potential strategy for designing emulsified foods based on the choice of ingredients and knowledge of the interaction between them.

Whey protein concentration by ultrafiltration and study of functional properties / Concentração de proteínas de soro por ultrafiltração e estudo das propriedades funcionais

ABSTRACT: This paper aim to evaluate the ultrafiltration (UF) process for constituents recovery from whey. Sequences of factorial designs were performed by varying temperature (5 to 40°C) and pressure (1 to 3 bar), to maximize the proteins concentration using membrane of 100kDa in dead end system. Based on the best result new experiments were performed with membrane of 50kDa and 10kDa. With the membrane of 50 the protein retention was about 3 times higher than the membrane of 100kDa. The concentrated obtained by UF membrane of 10kDa, 10°C and 2 bar in laboratory scale showed a mean protein retention of 80 %, greater protein solubility, emulsion stability and the identification of β-lactoglobulins (18.3 kDa) and α-lactalbumin fractions (14.2kDa). Therefore, the use of membrane of 100 and 50kDa are became a industrially recommendable alternatives to concentration of whey proteins, and/or as a previous step to the fractionation of whey constituents using membrane ≤10kDa, aiming at future applications in different areas (food, pharmaceutical, chemical, etc.).

RESUMO: O objetivo do estudo foi avaliar o processo de Ultrafiltração (UF) na recuperação dos constituintes do soro de leite. Planejamentos fatoriais sequenciais foram realizados, variando a temperatura (5 a 40°C), a pressão (1 a 3 bar) e visando maximizar a concentração de proteínas usando membrana de 100kDa em sistema dead end. Baseados nos melhores resultados, foram realizados experimentos com de 50kDa e 10kDa. Em relação a membrana de 50kDa, a retenção de proteínas foi cerca de três vezes maior em relação a membrana de 100kDa. O concentrado obtido por membrana UF de 10kDa, 10°C e 2 bar, em escala laboratorial, mostrou uma retenção média de proteína de 80%, maior solubilidade protéica, estabilidade da emulsão e a identificação das frações β-lactoglobulins (18.3kDa) e α-lactalbumin (14.2kDa). Portanto, o uso de membranas de 100 e 50kDa são alternativas recomendáveis industrialmente à concentração de proteínas de soro de leite, e/ou como etapa anterior ao fracionamento de constituintes do soro usando membrana ≤10kDa, visando aplicações futuras em difentes áreas (alimentícia, farmacêutica, química, etc).

Stability and in vivo efficiency of natural cosmetic emulsion systems with the addition of vegetable oils

The aim of the paper is to test stability and biophysical properties of hydrophilic and lipophilic emulsions with selected vegetable seed oils: Limnanthes alba, Prunus amygdalus dulcis, Cannabis sativa, Rosa rubiginosa and Hellianthus annuus. Biophysical properties of emulsions are investigated in vivo using non-invasive instrumental methods (corneometry, tewametry and pH) in a group of 12 healthy women volunteers. Their stability profiles (colour, phase separation and centrifugation) under various temperatures (9, 25, 37 and 57 °C) and storage time (24 hours, 2, 7, 14, 21 and 28 days) were monitored. The moisturising activities of the emulsions supplemented with various oils were comparable. The lipophilic emulsions showed a better ability to improve the condition of the skin barrier due to formation of a surface lipid film. The tested formulations regulated the pH of the skin towards neutral values. Lipophilic emulsions showed earlier phase separation and changes in colour. The greatest resistance to thermal stress during storage was observed for the emulsion bases. Emulsions containing oils, except for those with rosehip and hempseed oils, were stable up to the temperature of 37 °C. The studied emulsion systems are excellent vehicles of vegetable oils and exhibit relatively good stability, benefiting the natural properties of skin.